Credit: (left) DigitalGlobe; (right) British Antarctic Survey
Counting penguins isn't as hard as it might sound. (Hey, hold still!) Someone snaps a photograph of a colony and then marks up the picture to make sure that they aren't missing or double counting anybody. What is hard is getting to remote places, especially Antarctica. So a new approach is to use satellite images, and today researchers report the results of the first such comprehensive study. Scientists have found twice as many emperor penguins (Aptenodytes forsteri) as previously thought to exist, roughly 595,000 (plus or minus 81,000). They also came across seven new colonies (one shown at left), bringing the total to 44. To get the new number of birds, they had to enhance the images with a technique called pansharpening, which allowed them to distinguish between shadows, guano, and actual penguins. "This is a leap forward but it doesn't change the conservation concern [about] emperor penguins and many other species," says penguin expert P. Dee Boersma of the University of Washington, Seattle. "Unfortunately with climate warming and variation, we are likely to be studying the decline of emperor penguins. Satellite mapping will allow scientists to determine where the decline are occurring and by how much."
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